mk3 astra ecu fault codes

Hi, does anybody know how to read the ECU fault codes on a mk3 astra 1.6 16v
ecotec
without having a code reader?
Any help would be much appreciated.
Thanks
Guy

 

Most Vauxhalls still have a 'flash code' daignostic system incorporated -
even on very late vehicles although , it's capabilities are very limited. On
the late vehicles a 16-pin OBD type diagnostic connector is used. On most
cars , joining pins 6 & 5 together will the flash code sequence. On all late
cars , this ONLY works with the ignition on and the engine not running. The
limitation of this is that only 'stored' codes are accessible , so it is not
always possible to tie a stored fault code with a specific problem. The
other problem is that a non-running engine will always show a 'crankshaft
signal' or 'engine RPM' type fault simply because the engine isn't turning!.
This means that if these are the faults causing a vehicle problem , it is
not possible to identify them using 'flash codes'. The benefits of this
method over a proper scan tool is therefore limited.
Regards
Mike